31.5.09

Venetian Glass. - How they make Beads.

Scientific American 40, 14.6.1856

(Our Foreign Correspondence.)

Venice, Italy, April, 1850.

Venetian glass has a world-wide reputation, and since I have been here, I have spent some time in endeavoring to discover the reason why glass, manufactured in this city, should be any better than that produced elsewhere. As yet, I have not ascertained anything satisfactory, but conclude it is principally the colors introduced that give to this glass the name and same it has hitherto enjoyed. From a gentleman well acquainted with the glass trade, I learned that all the fine white crystal glass, used for decanters and table service, is imported into Venice from France and England, and that very little of the glass made here would compare with the manufactures of Germany and France.

Cntinuing my researches, I took an early opportunity of visiting some of the glassworks hereabours, where the articles produced were beads, bugles, fancy plates, bottles, cups, saucers, &c., beautifully colored but wanting in clearness, full of blemishes and air bibbles. The plate glass works employ only a few hundred men, and turn out an article thicker and superior to our ordinary window glass, but of a yellowish tint, denoting anything but real excellence. The great renown that Venice has obtained for glass works is chiefly owing to the immense number of beads manufactured in its establishments. Having visited all the large factories here, I will endeavor to descrine to you the process.

The materials are put into smaller furnaces than those used in America, but constructed upon the same principle, with contrivances for economising fuel, for which the Italians generally are celebrated. When the mass is sufficiently fused, the coloring pigment is thrown in, and mized with the molten glass. When thoroughly amalgamated, the workman garhers a couple of pounds of the melted matter upon the end of an iron rod, which he withdraws from the furnace and manipulates upon an iron slab; after this, he plunges the glass into a tub of water. When it is sufficiently cooled, he sticks it into the furnace again, where it remains until once more melted, then it is taken out and fashioned into a shape resembling a bottle, with the bottom broken out. Another workman now brings on a similar lump, attached to another rod; the two boys are welded together; then a couple of boys take each one of the rods, and "travel," in opposite directions, to either end of a long shed. As these boys run away from each other, the glass is drawn out into long tubular wires, so to call them, and lies along on the ground, where it is suffered to remain until cooled; after which it is broken up in lengths or tubes, three feet long, and sold to the bead and bugle makers, (a distinct class of operatives) or sent into other rooms of the same establishment, where workment break them into minute particles.

This operation is performed by men, women, and boys - who have before them an iron gauge, into which, with one hand, they thrust fifteen or twenty tubes, at the same time, and, with an iron instrument (resembling a hatchet head) in the other and, they rapidly chop off the ends of the tubes, according to the size adjusted on the gauge. These cuttings are then taken below, where they are put into an iron barrel along with some sand, and placed in a furnace over a pretty hot fire. A boy gives a revolving motion to the barrel, until the sharp edges of the choppings are sufficiently annealed, during which the speed of the rotary motion is progressively increased until the beads are properly shaped, when they are taken out of the barrel and polished, by being poured into bags and shaken from side to side by the force of two men - in the same manner that I have seen people, in this country, cleaning coffee and grain.

After polishing, the beads are sifted into sizes, and then some men, with light wooden trays, sort out the perfect specimens by a peculiar jerking motion, and slant which they dexterously give to the tray. The refuse is melted over again, and the now finished beads are put upon strings by a bumber of girls employed for that purpose. Various sizes are produced by larger or smaller tubes, as the case may be; but in all the operation is the same; the sifting process being necessary on account of the unevenness of the original tubes. The colors were very brilliant in some instances, but in all cases the glass seemed full of grits and blemishes, until toned down by the action of the fire in the second furnaces. May large warehouses receive the beads, where they are packed away in boxed for exportation. In one warehouse I saw several hundred tuns of them, filling barrels and boxes, or strongs of them piled away on shelves in compartments occupied by various colors. They were of all sizes, from the minutest mustard seed to the immense egg-like articles, exported to Africa and the Indies, for the use of the dusky beauties of those climes.

J. P. B.

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